USB Flash Drive not detected on a Windows 2003 machine

1. I have installed Windows 2003 on my machine.
2. It has CMI-8738 motherboard(pretty old).
3. When I insert the USB flash drive, it is not getting detected by the Windows 2003 Operating System.

I checked that there are no free USB drivers available on the net to install for 2003 with CMI 8738.

What could be the reason?